Vacuum release mechanism for refrigerated cabinet



June 24, 1958 R. EICHHORN ETAL i 2,840,261

VACUUM RELEASE MECHANISM FOR REFRIGERATED CABINET Original Filed May 11, 1955 2 Sheets-Sheet 1 INVENTORS.

R; L. EICHHORN ETAL June 24, 1958:

VACUUM RELEASE MECHANISM FOR REFRIGERATED CABINET 2 Sheets-Sheet 2 Original Filed May 11, 1955 1N VENTORS VACUUM RELEASE MECHANISM FOR REFRIGERATED CABINET Robert L. Eichhorn and Richard D. Verdick, Evansville, Ind., assignors, by mesne assignments, to Whirlpool Corporation, a corporation of Delaware Original application May 11, 1955, Serial No. 507,617, 7

now Patent No. 2,810,493, dated October 22, 1957. Divided and this application May 6, 1957, Serial No. 658,477

1 Claim. (Cl-,220-44) This invention relates generally to refrigerated cabinets, but is more specifically directedto a vacuum release of pressure equalizing means applicable for incorporation in such cabinets.

The present application is a division of our application, Ser. No. 507,617, filed by the same applicants May 11, 1955, with the same title, now Patent No. 2,810,493.

There is in wide use on the commercial markets today a low-temperature refrigerated cabinet, commonly. referred to as a vertical freezer, wherein the cabinet and food storage area are usually arranged with a front access opening that is covered with a hingedly mounted door or closure member, and such freezer cabinet most generally is adapted for maintaining temperatures in the order of zero degrees Fahrenheit therein. In order to economically maintain such low temperatures in these cabinets over appreciable lengths of time it was found necessary to minimize air leakage around the access opening thereof and, accordingly, a very efficient and highly effective gasket seal was developed. However, the application of such highly effective air sealing means forthwith introduced a new problem involving therelease or opening of the door because of pressure differences between the interior and the outside atmosphere, and the solution of; such problem forms an important feature of the present invention. g

It has been'found that when a verti al freezer cabinet of the type mentioned is either empty or nearly empty that the pressure differential between the interior and the exterior of the cabinet thereof maybecome sulficient to preclude or at least render diflicult the reopening of the access or entry door immediately after it has been closed. -It is believed this condition is brought about by the fact that when the door is opened the cold (zero degree) air in the cabinet falls out into the atmosphere, and then when the door is reclosed and the warmer air from the atmosphere outside the cabinet is forced thereinto the warm air iimmediately starts cooling and upon cooling contracts, thus reducing the pressure therewithin and forming a vacuum which must be overcome, preferably by equalizing interior and exterior pressures, before the door can again be readily opened. It was found in laboratory tests that it usually will require from five to six minutes before the air pressures inside and outside the cabinet are sufliciently equalized, through natural' leakage of air around the sealing gasket and otherwise,

to again permit easy opening of the door. At times, .of

this unusual but heretofore not generally problem.

It is an important object of the present invention, therefore, to provide novel and simplified means for rapidly equalizing air pressure differences between the"interio'r' and exterior of refrigerated cabinets.

Anothercbject is to provide pressure equalizing means between interior andexterior cabinet air pressures in afront opening type of refrigerated cabinet having a clo-" sure door hingedly mounted over said opening.

A further object is to provide a pressure-equalizing" device incorporated in the door of a refrigerated cabinet and which cooperates with the door actuating handle mechanism to permit equalization of air pressuresbe tween the interior and exterior of the cabinet.

A still further object is to provide an air passageway.

communicating with the interior and exterior of a re.- frigerated cabinet and to additionally provide means whereby said passageway may be selectively opened or closed to the passageof air from outside said cabinet.. A yet still further object is to provide means for. admitting air under atmospheric pressure into the interior of a refrigeratedcabinet in order to minimize the air pressure differential between the interior and exterior of said cabinet.

The foregoing and other objects and features of invention will become apparent as the disclosure ismore fully made in the following detailed description of apreferred embodiment of the invention and as illustrated inv the accompanying sheets of drawings in which: I

Figure 1 is a front elevational view of a refrigerated cabinetemploying the proposed invention; v Figure 2 is a top plan view of the refrigerated cabinets shown in Figure 1; I 1

Figure 3 is a partial sectional view of Figure 1 and shows generally the sealing tween the cabinet and the entry door;

Figure 4 'is a partial sectional view taken on line of Figure l and shows the application of a preferred:

embodiment of the proposed device to the 'door of.

A reference to the drawings will represented generally by the numeral 10. cabinet usually is fabricated with an inner-shell or liner 11 spaced from a similarly conformed outer shell or line:

12 and having heat insulating material 13, 'therebetween,

while the the marginal edges of said inner and outer'shells may be bridged with a breaker strip 13a of'anyysuitable well-known low-heat conducting plastic material'as is' well understood. The inner liner 11 is formed to define afood storage area or compartment, indicated generally by the numeral 14, having a front accessopening there into that is covered by an insulated entry door 15 which may be. hingedly secured to the cabinet by suitable means such as the hinges 16. The double-walled access door. 15 may be fashioned somewhat similarly to that of said? cabinet with an outer panel 17 spaced from an inner panel 18 and having heat. insulating material 19 in the space therebetween.

The marginal edges of the outer panel 17 of said door 2 may be secured by suitable conventional affixing means to a peripherally extending channel-like member 20,

whereasthe marginal edges of the inner panel 18 extend into a resilient gasket sealing member 21 and are suitably secured along with said gasket, by conventional means such asthe screws 22, to said channel member. If de sired, a suitable trim member, such as the resilient member shown at 23, may bejpositionedin'a peripherallyEex-' A 2,840,261 Patented June 24, 19 58 understood taken on line means ;b.e-

r 3 tending recess or opening 24 adjoining the forward marginal edge of the channel member 20.

Since the refrigeration apparatus plays no particularly nus al r91; neths. P sen ars tioni w not h w in the drawings and will not be described herein. Sufiice it, to say however, thatgany. conventional or well-known refrigeration system and apparatus may be used in its normalrnenner without deviating from any teachings or concepts of the instant invention. k e

The door is provided with a handle 25 pivotally mountedion the exterior thereof, which is adapted to actuate a generally. conventional latchingamechanism, indicated generally by the reference numeral 26, that engages and interlocks with-a strike 27 which, in turn, is

.afliitedtdthefcabinef 10; I An escutcheon-like frame or guardfrim 28f having an opening 29 therein is suitably positioned'oilet an opening. provided. in the inner door pan'el'member 18' iii the vici'nit'y. ot' the. said. latching mechanism; The opening 29 in-saidflescutcheon is prowithin said cabinet.

bers Hand 12, respectively, of said cabinet. The pedes- 1 talelike supportmembier 31 of saidlatch strike is dimensionedto project through an opening in the breaker strip member 131i and, ,if desired, an escutcheon-like frame 33 may be positioned"therearoundfor appearance-improving 'Tlielatching devicle 26; which is agenerally available item on the commercial rnarkets, is'fashioned with an outer casingor housing '3'4"whi ch supports and encloses a plurality of pivotally mounted "and sequentially motivated operating or-latch members 35; 36, 37 and 38; The latch casing M-may befixedly positionedjwithin the door, by suitable means such as the screws 39,-"'while"a" resilient gasket-like sealing padido'may be positionedbetween said casingand the-"outer door panel 1'7; An actuating plunger 4 1 "actuable by thelian'dleis slidably mounted inwabearing-member that issuitably secured to the door overlan opening in-the outerpanel thereof and said plunger is disposed to extend through an adjoining opening in a sidewall of the casing 34 so that the inner end ofssaid pluriger may engage the first operating member 35 of said 513N211 mechanismr A resilient bellows-like sealing boot 43, having outwardly extending flange portions thereonlthatarefixedly positioned between the said casing and said outer door panel, is 1 positioned over the adjoining openingsin said door p'anel and'casin'g andclosely surrounds the plunger -4l so as to perrnita sliding action thereofuwhile at-the same time sealing the area around said. plunger against-the admission ofair from outside of said cabinettothe interior thereof. The handle'25 which iS.JPlVOiQuY mOUl'ltCQ OH the; pin-43 has a heel-like portionlM whichlis diseposed to contact and engage the outer,

end =ofiwthe plunger 'fl upon movement of said handle A;resilient=lres,trainingmember, such as the-spring 45, is disposed to'bia's the handle to a position normally out of" Mounted, on a portion of the handle, disposed on the opposite 'side' of the pivot engagement zwithi said iplunger.

43rfrom that of theheel 44',--is a button-like sealing pad member 46 whichflis positioned to seat on and to sealotf orlaclose the opening 47through the door outer panel 17 together with the aligned opening 48 in a wallof the latch housing34 An opening49 in an opposite wall of said latchihousing is providedto accommodate the latch strike 27 I .whichiengages the holding or interlocking roller 50 that is -pivotally mounted on the latch member 38 formingzpai't of the said "latch mechanism. a f

In operation,when the door-15 is closed the gasketseal 21 .engagesand presses against the flanged over marginal edge portion' of the cabinet outer wall 12 and thereby provides an airseal-against the ingress and egress of air to and from the food storage compartment 14. As the air within said compartment subsequently cools it contracts and apressure difierential is established between the a cabinet air and that of the outside atmosphere; hence the subsequent breaking of the air seal provided by the gasket 21'is ordinarily accomplished only with great difliculty. With the present invention however, as the door handle 25 is grasped by the user and rotated around the pivot 43 to start the door opening operation the sealing button 46 is unseated by being raised off the opening 47 and, because the atmospheric air is at a higher pressure than that of the compartment 14, air from outside the cabinet will flow, in the path indicated generally by the broken arrow lines of Figure 4, through the aligned openings 47 and 48, through the interior of the housing 34 and the opening 49 in the opposite side thereof, and through the opening 29 in the inner door panel 18 to the reduced pressure areas The'inrush of air at atmospheric pressure into the cabinet tends to raise the pressure therein and thus equalizes the interior and exterior pressures. In this way the pressure differential between the compartment or cabinet air and the outside atmosphere is minimized and thus the vacuum like effect of the air seal is broken and the door may then be easily opened. By continuing the rotation of the handle 25 about its pivotal mounting pin 43'the heel 44 of said handle is made to engage and actuate the plunger 41 which then slides in its bearing member 42 to contact the first latch operating member 35 of the latch mechanism 26. The motion transmitted by said plunger to member 35, in turn, is transmittedsuccessively through members 36 and 37 to the last member 38 which upon rotation releases the keeper of holding roller 50 from its interlocking relationship with the strike 27 thereby permitting the door to be opened Since the latching mechanism is generally conventional in construction it is felt further detailed description of the components of its structure and operation is unnecessary for purposes of the present invention.

It should now be apparent that a novel pressure equalizing means has been shown and described, audit is to be understood that changes may be made in the construction without departing fromthe spirit ofthe invention or the scope thereof as defined in the appendedclaims;

What is claimed is: V e

In a combined refrigerator latch mechanism and air pressure release, the combination of a hook shaped strike to becarriedby a'refrigerator having a door with an outer panel adjacenta door opening, said strike having a transverse retaining shoulder and a beveled camming shoulder with alatch and pressure release mechanism comprising a latch housing to be carried by the back of said: outer'do'or panel, and said housing having a sealing gaske't to be positioned between the housing and-the outer panel of the door, saidgasket being clamped by threaded members securing said housing to saidouter doorl panel, closing an opening in said outer door panel,

' a door handle having a grip pivotally mounted on said housing to be located outside the door, an elongated tubular bearing membercarried by said housing and slidably supportingan actuating plunger for the latch, said plunger havinga headlocated to be engaged by a heel i ofthe door handle, said heel being located on the handle a latch pivoted on said housing to be retracted by engaging the beveled shoulder and to latch the door by engaging said transverse shoulder, a succession of pivoted levers acting on 'each othenand pivoted on said housing and arranged toactuate' said latch by means of said plunger,

spring means for moving said latch toward latching positionfspring means for urging the handle into a latched position'withsaid heel out of engagement with said 5 plunger, and a sealing pad carried by the rear of th handle on the grip thereof and located to engage and seal an opening extending through the outer door panel and through said housing to relieve the pressure difierential in the refrigerator by the initial movement of the handle, lifting said pad ofi said plunger before the heel of the handle engages said plunger or moves said latch, said pad automatically sealing said aperture upon release of the handle.

References Cited in the file of this patent UNITED STATES PATENTS Fate Feb. 12, 1907 Warren Feb. 22, 1938 Anderson et al Feb. 8, 1944 Maxson Aug. 19, 1947 Jacobson Dec. 28, 1954 

